20 meter yagi

Multiband Cubical Quads - EI7BA Multiband Cubical Quads projects, includes two elements quad antennas for 10 12 15 17 20 meters band. Performance considerations, detailed pictures and construction notes.

J-Vertical for 10 meters - A Slim Jim for 10 meters band

A 40m Vertical - This antenna is intended as a simple, inexpensive solution for the newcomer to experiment across the 40m band (7.0–7.2MHz) when only restricted space is available

80 meter loop antenna - PA1G loop antenna for 80 meters band, in dutch

A better antenna-tuner balun  ^pop - Which balun to use? The hybrid balun promises advantages over both voltage and current baluns by ZS1AN

20m QRP Dipole - Instructions to build a portable dipole for 20 meters

A Horn Antenna for 2.4 GHz. - This Antenna is not really practical for AO-40 reception, but horn antennas have a number of qualities useful in microwave antenna testing and noise figure measurements.

Windom off center fed antenna 80-10 mt - This antenna is not a true Windom, but rather an off center fed or OCF dipole works on 8 bands from 80 to 10 meters

Assembly of the Lightningbolt Quad - One of the best antenna values on the market is the LightningBolt Quad. At about half the cost of a tri-band yagi, you get five band coverage with a single coax feedline and excellent performance from a light, low wind load antenna.

A Modern Thermocouple Ammeter - Thermocouple ammeters are very rare these days, but the job they were perfect for - measuring antenna currents - is still a modern requirement especially in respect to groundplane currents. By David A. Reid PA3HBB G0BZF

Link Coupled Tuner - Legal Limit Link Coupled Balanced Tuner,for the amateur ham radio HF bands. This Tuner uses plug-in Coils sets for 40, 80, & 160 meters

Pringles Yagi Antenna - Design and build a Pringles Yagi antenna for 2.4Ghz.

PringlesCantenna - Seattle Wireless - The PringlesCantenna is an ultracheap Yagi-type directional antenna that can be built for under $10. The original Pringles Yagi was designed by Andrew Clap.

MicroTV Aerial - Seattle Wireless - Yagi antenna for 2.4Ghz band

JA1NLX Ham Radio - Ham blog from japan

TET-Emtron - Australian antenna manufacturer specialise in supplying amateurs with the best quality products. Amateur radio multiband Yagi antennas, balums, cb antennas, dipoles

CAL-AV Labs, Inc. - Cal-av labs, inc. (formerly california avionics laboratories, inc.) manufactures electronic instruments and systems for research and industry. we specialize in radio communications and research/electronic test products. Amateur radio yagi antennas, rotary dipoles, baluns, morse keys.

SAT-Service Schneider - Digital radio mondiale DRM products, measuring tools, Magnetic field probes, RF power meters, Broadband loop antennas, DRM devices and services

Nissei - VU Meter, Analog Meters, Panel Meter,Multi-Meter, SWR meter, power supply, power meters

Yagi Modeler Applet - This java applet/application implements a simple yagi modeling code. The initial input is a really trivial 2 elmenent yagi.

Logger32 for 11m - Logger32 special version dedicated to eleven meters band operations

Delabs technologies Product Design and Engineering - Around 200 electronic circuits in pdf format or images, There are also over 1000 links to useful electronics, freeware, open source websites. There are some 100 useful documents, software and pcbs too. Mainly industrial electronics, instrumentation. Covers Various aspects of electronics and basics of circuit design.

A low pass filter circuit - A simple 7 element, Chebyshev low pass filter, rolls of at 30MHz. Attenuation is better than -40dB at 60MHz, -65dB at 90MHz, -80dB at 120MHz.

A CW TX for 80 meters band - This simple circuit will give about 1.2 Watts of output when powered from a 13.8VDC supply.

Prototype SWR meter for 2.45Ghz - Testing antenna's is a lot easier if you have a good swr meter this is a prototype of a design by g7eyt.